Objectives The purpose of this study was to evaluate the ultrasonographic characteristics of metastatic lymph nodes in patients with papillary thyroid carcinoma. Methods The ultrasonographic characteristics of lymph nodes were analyzed in 112 consecutive patients who underwent thyroidectomy and lymph node dissection, with the diagnosis being confirmed by anatomopathologic examination. Results A total of 198 lymph nodes were metastatic, and 152 were benign (normal or with nonspecific lymphadenitis). Minimum axial diameters of 7 mm for level II (upper internal jugular chain) and 6 mm for the rest of the neck were observed in 93% of metastatic lymph nodes, absence of an echogenic hilum in 88%, hyperechogenicity in relation to the adjacent muscles in 86%, a round shape in 80%, calcifications in 49.5%, and intranodal cystic necrosis in 20%. These ultrasonographic characteristics were observed in 17%, 10%, 4.5%, 29.5%, 0%, and 0% of benign lymph nodes, respectively. Conclusions Even basic ultrasonographic characteristics (shape, echogenicity and echogenic hilum, calcifications, and intranodal cystic necrosis) help in the differentiation between metastatic and nonmetastatic lymph nodes in patients with papillary thyroid carcinoma.

Thyroid nodules are frequent findings, especially when sensitive imaging methods are used. Although thyroid cancer is relatively rare, its incidence is increasing, particularly in terms of small tumors, which have an uncertain clinical relevance. Most patients with differentiated thyroid cancer exhibit satisfactory clinical outcomes when treatment is appropriate, and their mortality rate is similar to that of the overall population. However, relapse occurs in a considerable fraction of these patients, and some patients stop responding to conventional treatment and eventually die from their disease. Therefore, the challenge is how to identify the individuals who require more aggressive disease management while sparing the majority of patients from unnecessary treatments and procedures. We have updated the Brazilian Consensus that was published in 2007, emphasizing the diagnostic and therapeutic advances that the participants, representing several Brazilian university centers, consider most relevant in clinical practice. The formulation of the present guidelines was based on the participants' experience and a review of the relevant literature.

Recently, it was proposed that some papillary thyroid carcinomas (PTC) will no longer be termed ‘cancer’ and are christened as ‘noninvasive follicular thyroid neoplasm with papillary-like nuclear features’ (NIFTP). As this is a recent definition, little information is available about NIFTP. The objective of this study was to report the frequency, ultrasonographic appearance, cytology result and long-term evolution of cases of NIFTP seen at our institution. We excluded tumours ≤1 cm. The sample consisted of 129 patients. Sixty-four patients were submitted to total thyroidectomy and 65 to lobectomy. These patients with NIFTP did not receive radioiodine. NIFTP corresponded to 15% of cases diagnosed as PTC >1 cm. An ultrasonographic appearance considered to be of low suspicion for malignancy was common in NIFTP (32.5%), whereas a highly suspicious appearance was uncommon (5%). NIFTP frequently exhibited indeterminate cytology (62%), while malignant cytology was uncommon (4%). The patients were followed up for 12–146 months (median 72 months) after surgery. None of the patients developed structural disease during follow-up. Comparing the concentrations of thyroglobulin (Tg) and anti-Tg antibodies (TgAb) obtained 6–12 months after surgery and in the last assessment, none of the patients exhibited an increase in these markers.

Preparation with recombinant human thyroid-stimulating hormone (rhTSH) for thyroid remnant ablation results in lower extrathyroidal radiation than does hypothyroidism. The objective of this prospective study was to compare the damage caused by ¹³¹I (3.7 GBq) when these 2 preparations are used. Methods: Ninety-four consecutive patients who underwent total thyroidectomy and remnant ablation with 3.7 GBq of ¹³¹I were studied. Thirty patients (group A) received rhTSH, and 64 (group B) were prepared by levothyroxine withdrawal. Damage to salivary glands, ovaries, and testes; hematologic damage; and oxidative injury were evaluated by measurement of serum amylase, follicle-stimulating hormone (FSH), complete blood count, and plasma 8-epi-PGF_2α before and after radioiodine. The 2 groups were similar in sex, age, and the results of baseline assessment. Results: The rate of successful ablation (stimulated thyroglobulin level < 1 ng/mL and negative findings on neck ultrasonography) was 90% in group A and 80% in group B. Considering only patients with a preablation thyroglobulin level greater than 1 ng/mL, these rates were 80% and 70.6%, respectively. Only 1 patient (3.3%) reported transient headaches with rhTSH. Elevated FSH levels after therapy were observed in 4 of 9 (44%) men in group A versus 16 of 18 (89%) in group B (P < 0.03), with a mean increase of 105% versus 236% (P < 0.001), respectively. In women, elevated FSH was observed in 1 of 13 (7.7%) patients in group A versus 6 of 30 (20%) in group B (P = 0.4), with a mean increase of 65% versus 125% (P < 0.001). Thrombocytopenia or neutropenia occurred in 2 of 28 (7%) patients in group A versus 12 of 56 (21.4%) in group B (P = 0.1), with a mean decrease of 20% versus 45% and 25% versus 52% (P < 0.01) for neutrophils and platelets, respectively. Hyperamylasemia and symptoms of acute sialoadenitis occurred in 11 of 30 (36.6%) versus 48 of 60 (80%) (P < 0.001) and in 9 of 30 (30%) versus 35 of 60 (58.3%) (P = 0.01), respectively. 8-Epi-PGF_2α was found to be elevated after ¹³¹I in 14 of 25 (56%) patients in group A versus 45 of 45 (100%) in group B (P < 0.001), with a mean increase of 60% versus 125% (P < 0.001). Conclusion: The lower radiotoxicity with rhTSH, suggested in dosimetry studies, was confirmed in the present prospective investigation, and this advantage occurred without compromising the efficacy of treatment.

Background: This study investigated the value of postoperative stimulated thyroglobulin (Tg) combined with neck ultrasonography for the prediction of the posttherapy whole-body scanning (RxWBS) and the efficacy of ablation with 30 mCi ¹³¹ I in patients with thyroid cancer and low risk of recurrence to identify those who do not require ablation or only need a low ¹³¹ I activity. Methods: A total of 237 consecutive patients with well-differentiated thyroid cancer and low risk of recurrence who were initially treated by total thyroidectomy followed by remnant ablation with 1.1 or 3.7 GBq (30 or 100 mCi) ¹³¹ I were studied. Neck ultrasonography, Tg after levothyroxine withdrawal, and anti-Tg antibodies (TgAb) were obtained before, and RxWBS was performed 7 days after ¹³¹ I administration. Patients with TgAb were excluded. Results: Postoperative ultrasonography revealed lymph node metastases in 5/237 (2%) patients. RxWBS showed ectopic uptake in 3/232 (1.3%) patients with negative ultrasonography. The negative predictive value of postoperative stimulated Tg <1 ng/mL ( n = 132) or <10 ng/mL ( n = 213) combined with negative ultrasonography was 100%. Among patients with detectable postoperative stimulated Tg <10 ng/mL and negative ultrasonography, 50 received 1.1 GBq ¹³¹ I and 31 received 3.7 GBq. In the control assessment, stimulated Tg <1 ng/mL and neck ultrasonography without anomalies were achieved in 47/50 (94%) and in 29/31 patients (93.5%). All patients with stimulated Tg ≤1 ng/mL, negative TgAb, and normal ultrasonography before ablation continued to show the same results 8–12 months after initial therapy as expected, irrespective of the administration of 1.1 GBq ( n = 82) or 3.7 GBq ¹³¹ I ( n = 50). Conclusions: Measurement of stimulated Tg combined with neck ultrasonography after total thyroidectomy may exclude the need for ablation in 56% of low-risk patients without TgAb (Tg <1 ng/mL) and permit the administration of an activity of 1.1 GBq ¹³¹ I in another 34% with low Tg levels.